This invention relates to a motor reversing plug connector, particularly for use with three-phase alternating current motors.
Reversal of direction of rotation of three-phase motors is accomplished by simply reversing two of the three line connections to the motor. In permanent installations, particularly where the need to reverse rotational direction is infrequent, no special means are ordinarily provided to rapidly reverse the external connections of the motor. However, should the need arise, it is then necessary to remove the cover plate of the connection box and manually reverse two of the three line connections to the motor. On the other hand, where a machine being driven by a three-phase motor must be reversible during use, this is usually accomplished either by providing a reversible transmission; or the same can be accomplished with a double-pole-double-throw switch in the circuit, connected to reverse two of the three leads to the motor. Both of these systems generally are intended for relatively permanent installations and can become somewhat cumbersome where portability or mobility are desired.
It is, accordingly, one object of this invention to provide an inexpensive, easily-manipulated reversing connector for a three-phase system. Another object is to provide such a connector having ground pins so located as to permit reversal of phase while maintaining the ground connections in either direction. A further object is to provide a connector permitting the use of readily available four-conductor cable in which one of the conductors is used for grounding purposes. Yet another object is to provide a connector which can be effectively sealed against entry of water and which is not easily pulled apart by accident.
The foregoing and other objects which will become apparent to those skilled in this art are accomplished by means of the present invention which will be more fully understood from the description below and from the accompanying drawings: